Overview

In the opening cutscene of Sonic and the Black Knight, King Arthur dispatches Sir Percival, Sir Gawain, and Sir Lancelot to hunt down and kill Sonic and Merlina. Percival and Gawain express misgivings, but nevertheless obey. The anthropomorphic cat is the final Knight to face Sonic and Caliburn; in fact, it is Sonic who eventually hunts her down in Molten Mine, after Nimue reveals that Laevatein is required to negate the power of the Scabbard of Excalibur. Percival is perhaps the most difficult of the initial Knights of the Round Table battles; like her dimensional counterpart, she can use pyrokinesis to wreathe herself in flames, foiling any attempt at offense.

Sonic manages to defeat the Knight of the Grail in battle, and Percival is forced onto a precipice above a lava lake. While admitting her defeat, the knight loses her footing and tumbles towards molten death. Sonic dives over the cliff face to save her by digging Caliburn into the rock wall - an act of chivalry which finally convinces the sentient sword that Sonic is worthy of being called a knight himself.

Despite losing her sword and owing Sonic her life, Sir Percival persists in her mission to locate and slay the Royal Wizard, Merlina. While Sonic battles King Arthur on Faraway Avalon, the Knights of the Round Table corner Merlina within Camelot Castle, before she reveals herself as the Dark Queen. In order to save the Grand Kingdom from Merlina's vision of magical stasis, the Knights team up with Sonic and Nimue to activate four enchanted stones; Percival speeds off towards the one in The Cauldron.

Gameplay

Pecival's style of fighting is mostly ground-based. Her rapier style allows her to strike with quick slashes and jabs, but her aerial attacks are mostly an arrow like stab. She can also double jump & use homing attack to cross longer distances than Sonic or Lancelot; a somewhat useful tactic in "Don't Touch The Ground" missions, and in Shrouded Forest where it can be used to avoid the magical vines which sprout along the floor.

Her Soul Gauge move, Flames of Kilekion, has her spinning in a flaming tornado, similar to Blaze in Sonic Rush. She can only use this move on the ground, but when it strikes ground foes it registers a Perfect Hit. While this technique doesn't allow her much speed while attacking like other Sonic or Lancelot, She can still run incredibly fast when not attacking.

Trivia

In the real-world King Arthur/Holy Grail legends, Sir Percival was male and the brother of Sir Lamorak.